"As we fill our days with more and more 'doing', many of us are finding that non-stop activity isn't the apotheosis of productivity. It is its adversary. Researchers are learning that it doesn't just mean that the work we produce at the end of a 14-hour day is of worse quality than when we're fresh. This pattern of working also undermines our creativity and our cognition. Over time, it can make us feel physically sick -- and even, ironically, as if we have no purpose. [...] One meta-analysis found that long working hours increased the risk of coronary heart disease by 40% -- almost as much as smoking (50%)"